Honda Motor Co. and Isuzu Motors Ltd. said Wednesday they have agreed to conduct joint research on fuel cell-powered heavy-duty trucks, in another collaborative move in the auto industry which has seen fierce competition for eco-friendly vehicles.

Honda R&D Co. and Isuzu signed the agreement to promote fuel cells as the powertrain at a time when hydrogen stations are still limited in Japan.

Isuzu has been looking to enhance the lineup of its trucks to respond to growing demand for self-driving and low-emissions vehicles, while Honda, which makes Clarity fuel cell cars, seeks to expand the application of its fuel cell technology beyond use for passenger vehicles.

Fuel cell vehicles are seen as one of the most promising green cars as they run on electricity generated from a chemical reaction of hydrogen and oxygen and emit only water.

Honda and Isuzu said that "the use of fuel cell trucks and hydrogen energy can contribute to the future prosperity of the logistics industry and all other industries in our society and to the early realization of a hydrogen society."

Toyota Motor Corp., which introduced the world's first mass-produced fuel cell car, the Mirai, in 2014, also promotes next-generation technology. It seeks to boost global sales of fuel cell vehicles to 30,000 a year sometime after 2020.

Toyota said last year it will supply its fuel cell technology to Beijing Automotive Group Co. in a bid to expand business in China, the world's largest auto market by volume.

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